Metabolic and behavioral effects of high-dose, exogenous testosterone in healthy men

Abstract:

In addition to their use as replacement therapy for hypogonadal males,
androgens, particularly testosterone (T), are being explored as potential
hormonal male contraceptive agents, alone or in combination with other
compounds. Androgens have regulatory effects on a variety of physiological
systems in addition to gonadotropin secretion and spermatogenesis.
Therefore, as hormonal contraceptive regiments that alter serum T levels
are explored, it is important to evaluate their effects on these aspects
of normal male physiology. The effects of exogenous T on suppression of
spermatogenesis in 19 healthy men were recently compared, using a T dosage
of 200 mg im/week for 20 weeks. Before treatment, the men were evaluated
during a 3-month pretreatment period, and after treatment, they were
followed for 4-6 months or until their sperm counts normalized. Because of
the lack of information regarding the effects of exogenous T on
nonreproductive physiology, we examined the effects of high-dose T on
plasma lipids, calcium metabolism, and sexual behavior in our subjects.
Mean serum T and estradiol levels increased significantly during the
treatment period. Plasma high-density lipoprotein (HDL) cholesterol levels
decreased significantly within the first month and remained suppressed
during the duration of T administration. At the end of the treatment
period, mean plasma HDL cholesterol had decreased by 13 +/- 2% (P < 0.05);
plasma levels of HDL2, HDL3, and apoprotein AI also decreased
significantly; mean levels of low density lipoprotein cholesterol and
triglycerides were unchanged. After 1 month of the recovery period, plasma
HDL levels had returned to the baseline range. Serum calcium levels
decreased slightly during treatment; this decrease was statistically
significant. Urinary calcium excretion did not change. Mean levels of
serum intact PTH increased by 84 +/- 17% (P < 0.05) during T
administration; in contrast, 25-hydroxyvitamin D levels decreased by 16
+/- 4% (P < 0.05), and 1,25-dihydroxyvitamin D levels did not change
significantly. All markers of calcium metabolism returned to baseline
during the posttreatment period. Little change was found in self-reported
sexual and aggressive behaviors during the study. There was a trend toward
increased arousal and spontaneous erections during T administration, but
this did not reach statistical significance. Frequency of sexual
intercourse, masturbation, and kissing and fondling did not change, nor
was the subjects' satisfaction in their relationships affected by T
administration. Mean body weight increased by 4.0 +/- 0.5 kg.
Approximately half the men noted mild acne. Body weight and acne symptoms
returned to baseline during the recovery period.(ABSTRACT TRUNCATED AT 400
WORDS)